Plain English Meaning

A spiral shape that moves forward as it spins, like the path a screw cuts as it's driven into wood.

Full Definition

A three-dimensional curve that winds at a constant angle around a central axis, advancing along that axis as it turns — the shape traced by the tip of a propeller blade as the aircraft moves forward through the air.

Context Anchor

Seen in aircraft maintenance when describing coiled springs, screw threads, and the twisting path of air behind a propeller.

Derivation

From the Greek 'helix,' meaning a spiral or twist. The same root gives us 'helicopter' (literally 'spiral wing'). Knowing the root helps because it together several terms that all involve , spiral motion.